Electric radiant heater



Patented Sept. 29, 1925.

UNITED STATES PATENT oFFlcE.

ORA A. COLBY, 0F IRWIN, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOU'SE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRIC RADIANT HEATER.

Applicationled May 24, 1923. Serial No. 641,061.

To all whom t may concern Be it known that I, ORA A. CoLBY, a citi- .zen of the United States, and a resident of Irwin, in the county of Westmoreland and State of Pennsylvania, have invented a new and useful Improvement in Electric Radiant Heaters, of which the following is a specification.

My invention relates to electrical heating devices and particularly to electric air heaters.

One object of my invention is to provide an electric air heater of relatively simple structure and of relatively large distributed capacity.

Another object of my invention is to provide an electric air heater comprising a plurality of independent heating elements.

Another object of my invention is to provide an electric air heater comprising a plurality of independent heating elements, each element comprising a skeleton frame having a plurality of spaced, parallel-extending `bars on which a resistor member is located.

Another object of my invention is to provide a heating element comprising a refractory supporting means of such form as to provide relatively small heat storage capacity and effective to support a substantially uniformly distributed radiant resistor member. Y

In practicing my invention, I provide a suitable casing having a front opening therein, and a plate of refractory electricinsulating material in said casing back of said front opening.

I provide a plurality of skeleton frames, of refractory electric-insulating material, each frame comprising a plurality of spaced, parallel-extending bars. Ahelically wound resistor member is wound in helical c onvolutions upon the respective bars of the skeleton frames that may be provided with integral spaced lugs or bosses to separate the adjacent turns of the resistor member on the individual bars, from each other.

I provide a suitable switch to control the energization of the heating elements, such switch being located on the outside of said casing.

In the single sheetof drawings,

Figure 1 is a view,'in front elevation, of an electric air heater comprising the device embodying my invention,

Fig. 2 is a view, in vertical lateral section herethrougm taken on the line II-II of Fig. 3 is a partial view, in front elevation, of a modified form of device embodying my invention,

Fig. 4 is a view, in vertical lateral section zherethrough, taken on the line IV-IV of tig. 3,

Fig. 5 is a partial enlarged view, in front elevation, of a heating element comprising a refractory skeleton frame and a resistor member located thereupon, and

Fig. 6 is a partial enlarged sectional view through one of the supporting bars of the skeleton frame illustrated in Fig. 5, showing particularly the integral bosses located thereon.

An electric air heater ing 12 that may be built or desired manner, either metal members or by the use of metal castings combined to form a casing having an ornamental and pleasing appearance. The casing 12 may be located on a base 13 hav- 11 comprises a casup in any suitable by the 'use of sheet Ving integral supporting members 14.

A cover member 15 is provided that may be removable from the rest of the casing to permit of mounting the other parts of the heater therein. The top or cover member 15 is of such form and construction as to harmonize with the casing 12.

The casing 12 is provided with a depressed front portion 16 having an opening 17 therein. A grating 1S is provided in the depressed portion 16 and comprises a plurality of vertically and of horizontally eX- tending rods or wires suitably secured together to constitute a skeleton frame.

The upper ends of the vertically extending bars are loosely fitted into a plurality of spaced and co-operating openings 19 in the top part of the depressed portion 16. A plurality of spaced openings 21 is provided in the low er part of the depressed portion 16 into which the lower ends of the vertically extending rods may lit loosely, a horizontally extending rod 22 secured to the grating being provided to suitably locate the grating in the respective openings 19 and 21. The length of the vertically extending rods or wires is such that the grat ing may be mounted in its proper operative position by first placing the upper ends thereof in the cooperating openings 19, then raising the grating a suilicient amount to permit of the lower ends entering the lower openings 21, whereupon the grating is permitted to drop to its proper operative posi tion substantially as illustrated in Figs. 2 and l of the drawing.

A plate 23, of a suitable refractory elec tric insulating material which is provided within the casing l2, constitutes a reflector for the heating elements to be hereinafter described. The plate 23 is held in its proper operative position back of the front opening 17 by any suitable means, such as a refractory plate or bar 24 located therebeneath. Any suitable or desired means may be provided for holding the plate 24 in substan- Jtially the position illustrated in the drawings.

A plurality of heating elements are located in the casing in front of the refieetor plate 23 and severally comprise a skeleton frame 25 of refractory electricinsulating material and a helically wound resistor member 26. Each of the skeleton frames comprises integral end portions 27 and side portions 28 constituting a rectangular frame. A plurality of spaced bars 29 integral with the ends 27 extend longitudinally of the skeleton frames 25 thaty are substantially rectangular in contour and that may be of any suitable or desired width and length.

The integral bars 29 are each provided on one surface thereof, for instance at the front of the frames 25, with a plurality of spaced integral bosses 30. The helically wound resistor members 26 are helically wound on the respective bars 29, the bosses 30 serving to insulate adjacent turns of the resistor member from each other, or in other words, to maintain the adjacent turns in a predetermined position on the bars and relatively to each other.

As illustrated in Fig. 1, the skeleton frames may be so supported in front of the reflector plate 23 that the bars 29 extend in a substantially horizontal direction. -lff desired, the skeleton frames 25 may, however, be so located in the casing that the bars 29 extend in a substantially vertical direction, as illustrated more particularly in Fig. 3 of the drawing. A plurality of open: ings 31 may be provided at the corners of the skeleton frames to permit of securing them against the reflector plate.

rlhe dimensions of the helical resistor member 26 and of the bars 29 and the spacing between the adjacent turns of the re spective supporting bars 29 are such that substantially uniformly distributed heating units are obtained and any desired relative location of the turns of the resistor member on the adjacent supporting bars may be employed to still further distribute the winding over the available surface.

Any desired number of resistor members 2G may be employed not only in accordance with the voltage of the supply circuit to which the electric heater embodying my invention is to be connected, but also in ac cordance with the method of control of the individual heating units.

A means for controlling the supply of energy to the heating elements may' comprise a switch 32 that is ,suitably secured against a face plate 33 which is, in turn, suitably secured against a side portion of the casing 12 by a plurality of screws A pair of bus bars 35 and 36 may be suitably mounted in the casing 12 in either a substantially vertical position, as illustrated in Figs. 1 and 2 of the drawing, or in a substantially horizontal position, as illustrated in Figs. 3 and et of the drawing and be suitably supported therein.

The ends of the individual heating units 26 may be made sufficiently long to permit of their being secured to the respective bus bars 35 and 36 by ysuitable means, such as machine screws 37. Terminal pins 33 may be mounted on the plate 33 of electric-insulating material to permit of easily and quickly connecting the terminals of a supply circuit, not shown, thereto. The termina-l pins 38 are suitably connected to the control switch 32 and to the bus bars 35 and 36 to permit of suitably controlling the supply of energy to the individual heating units.

The device embodying my invention thus provides a plurality of relatively simple and compact individual heating units that may be easily and quickly removed from and replaced in their proper operative position and that severally provide a heating element comprising a substantially uniformly distributed heating unit located therein.

Various modifications and changes may be made without departing from the spirit and scope of the invention and I desire, therefore, that only such limitations shall be placed thereon as are imposed by the prior art or are set forth in the appended claims.

I claim as my invention:

1. In an electric heater, in combination, a casing having an open front, a reflector plate, of refractory material, in said casing adjacent said open front, and a plurality of radiant heating elements in said casing in said open front, each heating element conv prising a refractory skeleton frame having a plurality of spaced, parallel, bars, and a helical resistor member helically Wound on said bars.

2. In an electric heater, in combination, a casing having an open front, a reflector plate, of refractory material, in said casing adjacent said open front, and a plurality of radiant heating elements in said casing in said open front, each heating element 10 comprising a refractory skeleton frame having a plurality of spaced, parallel, bars, each of said bars having integral, spaced, lugs thereon and a helical resistor member helically Wound on said bars between said lugs.

n testimony whereof, I have hereunto subscribed my name this 21st day of May, 1923.

ORA A. COLBY. 

